WO2022012082A1

WO2022012082A1 - Light source module for laser radar, laser radar, and method for manufacturing light source module

Info

Publication number: WO2022012082A1
Application number: PCT/CN2021/082803
Authority: WO
Inventors: 朱雪洲; 刘建峰; 尹辉; 向少卿; 孙恺
Original assignee: 上海禾赛科技股份有限公司
Priority date: 2020-07-14
Filing date: 2021-03-24
Publication date: 2022-01-20
Also published as: CN113933812A; CN116990783A

Abstract

A light source module (20) for a laser radar. The light source module comprises: a driver chip (21) and a laser unit (22), wherein the laser unit (22) is stacked on the driver chip (21), and is electrically connected to the driver chip (21), so as to be driven by the driver chip (21) to emit laser light. Further provided are a laser radar that comprises a light source module (20), and a method for manufacturing the light source module (20).

Description

Light source module of laser radar, laser radar and method of manufacturing light source module

technical field

The present invention generally relates to the technical field of laser radar, and in particular, to a light source module of a laser radar, a laser radar including the light source module, and a method for manufacturing the light source module.

Background technique

In pulsed lasers, the pulse width is primarily limited by the parasitic inductance of the laser drive loop. In the current LiDAR, the laser and the driver chip are arranged in parallel on the printed circuit board (PCB), that is, on the surface of the PCB, the laser and the driver chip are laid flat, and there is no direct electrical connection between each other, but through The laser is connected to the bonding pad of the PCB, and the driver chip is connected to another bonding point of the PCB. The two bonding points are electrically connected by the PCB leads, so that the anode and cathode of the laser are electrically connected to the driver chip respectively. MOSFET and GND. The multiple bonding wires and PCB leads included between the laser and the driver chip make the drive loop very long. The parasitic inductance generation paths include loop inductance, mutual inductance, and vias. The longer the electrical loop, the greater the loop inductance. big. The parasitic inductance is thus increased, resulting in a broadening of the laser pulse. Using GaN-driven lasers, GaN is also connected between the driver chip and the laser, and the electrical circuit is further lengthened and the inductance is larger. Fig. 1 shows the arrangement of lasers, driver chips, and printed circuit boards in the current lidar. As shown in FIG. 1 , a plurality of lasers 102 are fixed on a printed electronic circuit board (PCB) 103 and are electrically connected by leads 104 on the printed electronic circuit board 103 . Specifically, a plurality of lasers 102 and driver chips 101 are tiled (arranged in parallel) on the printed electronic circuit board 103, the lasers 102 are connected to the bonding pads 105 of the printed electronic circuit board 103, and the driver chips 101 are connected to Another bonding point 105 connected to the wire is electrically connected by the lead 104 of the printed electronic circuit board 103 to electrically connect the two bonding points 105, so as to electrically connect the anodes and cathodes of the plurality of lasers 102 to the driver chip 101 respectively. The driver chip 101 drives the laser to emit light.

The inductance L1 of the PCB bonding wire is ≈ 1nH/mm, and the inductance L2 of the PCB trace is equal to 0.002S(2.3lg(2S/W)+0.5)μH (where S is the line length and W is the line width). It can be seen that the plurality of bonding wires 106 and the PCB leads 104 included between the plurality of lasers 102 and the driver chip 101 in the prior art make the driving loop very long, thereby increasing the parasitic inductance. For the pulsed semiconductor laser, di/dt=V/L, where di/dt is the rising rate of the driving current, V is the operating voltage of the driving circuit, and L is the total inductance of the discharge loop. The higher the rising rate of the driving current, the steeper the rising edge of the laser pulse, the higher the slope, the shorter the on-time, and the narrower the corresponding pulse width.

In lidar products, due to the constraints of human eye safety and the constraints of the total power consumption/heating of the product, the narrower the laser pulse and the higher the peak power that the driving circuit can emit, the better the distance measurement ability and distance measurement will be obtained. precision. A laser with a narrower pulse width can measure farther under the condition of the same pulse energy, or use less pulse energy under the same ranging capability, which is easy to meet the requirements of human eye safety. Therefore, in order to reduce the laser pulse width, the drive loop inductance must be reduced.

One of the current development trends of lidar is that the number of lines is getting higher and higher, and linear array scanning lidar also has such a trend. This means that the number of transceiver measurement channels of the lidar will continue to increase, but the product volume will not change significantly, that is, the number of lines will be increased by increasing the channel density. This poses a challenge to the integration of the driver circuit and the transmitter subsystem. The layout of the laser and driver chips paralleled on the PCB requires a large surface area of the PCB, and more channels require a larger area of the PCB, and the volume of the transmitting subsystem increases, which is not conducive to multi-channel lidar. integration. Moreover, as the number of transceiver measurement channels increases, the wiring on the PCB becomes more complex, and the influence of parasitic elements increases further.

The contents in the Background section are merely technologies known to the disclosed person, and do not of course represent the prior art in the field.

SUMMARY OF THE INVENTION

In view of at least one defect of the prior art, the present invention provides a light source module that can be used for lidar, including:

driver chip; and

a laser unit, which is stacked on the driver chip and electrically connected to the driver chip, so that the laser can be driven by the driver chip to emit laser light.

According to an aspect of the present invention, wherein the driver chip is a multi-channel driver chip, and the laser unit includes an array formed by a plurality of lasers.

According to an aspect of the present invention, wherein the plurality of lasers share a cathode, the cathode is electrically connected to the ground terminal of the multi-channel driver chip, and the plurality of anodes of the plurality of lasers are respectively electrically connected to the multi-channel driver Multiple bond points of the chip.

According to an aspect of the present invention, the light source module further includes a plurality of control circuits, the multi-channel driver chip includes a control logic unit, and the plurality of control circuits are respectively connected to a plurality of the plurality of lasers through a switching device. The anode, the control logic unit of the multi-channel driver chip is electrically connected to the plurality of control circuits, so that the plurality of lasers are controlled to emit light independently by the plurality of control circuits.

According to one aspect of the present invention, wherein the electrical connection comprises soldering with bond wires.

According to an aspect of the present invention, the light source module further includes:

The electrically connected light source modules are packaged with a packaging material.

According to an aspect of the present invention, wherein the electrical connection includes pre-bonding of insulators and metal bonding on the bonding surfaces of the laser unit and the driver chip.

According to one aspect of the present invention, the laser unit includes one or more of a vertical cavity surface emitting laser and an edge emitting laser.

According to one aspect of the present invention, the vertical cavity surface emitting laser includes one or more of single-cavity VCSEL and multi-cavity VCSEL.

The present invention also provides a laser radar, including the above-mentioned light source module.

The present invention also provides a method for manufacturing a light source module, comprising:

Stack the laser unit on top of the driver chip;

The laser unit is electrically connected to the driver chip.

According to one aspect of the present invention, wherein the driver chip is a multi-channel driver chip, the laser unit includes an array formed by a plurality of lasers, and the step of electrically connecting the laser unit to the driver chip includes:

the plurality of lasers share a cathode, and the cathode is electrically connected to the ground terminal of the multi-channel driver chip;

The plurality of anodes of the plurality of lasers are respectively electrically connected to the plurality of bonding points of the multi-channel driver chip.

According to one aspect of the present invention, wherein the light source module includes a plurality of control circuits, the multi-channel driver chip includes a control logic unit, and the step of electrically connecting the laser unit to the driver chip further includes:

connecting the plurality of control circuits to the plurality of anodes of the plurality of lasers through switching devices, respectively;

The control logic unit of the multi-channel driver chip is electrically connected to the plurality of control circuits.

According to one aspect of the present invention, the manufacturing method further includes:

A preferred embodiment of the present invention provides a light source module formed by stacking a laser unit and a driver chip, a laser radar including the light source module, and a method for manufacturing the light source module. The light source module provided by the present invention can realize the electrical connection between the laser and the driver chip without wiring from the PCB, thereby reducing the parasitic inductance of the driving circuit, thereby realizing the emitter narrow laser pulse, and improving the distance measurement performance and the performance of the laser radar product. The accuracy of ranging, the resolution point frequency is reduced, and the pressure on the human eye safety threshold is relieved. The stacking design improves the integration of the light source module, facilitates automatic assembly and production, and can better adapt to the development trend of multi-channel and independently addressable lidars for each channel.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the specification, and are used to explain the present invention together with the embodiments of the present invention, and do not constitute a limitation to the present invention. In the attached image:

Fig. 1 schematically shows a light source module composed of a laser and a driver chip arranged in parallel on a printed electronic circuit board in the prior art;

Fig. 2 schematically shows a light source module formed by stacking laser units on a driver chip according to a preferred embodiment of the present invention;

3 schematically shows a top view of a light source module formed by stacking laser units on a driver chip according to a preferred embodiment of the present invention;

4 schematically shows the internal circuit structure of a light source module formed by stacking laser units on a driver chip according to a preferred embodiment of the present invention;

FIG. 5 schematically shows a connection manner of bonding the laser unit to the driver chip by bonding wires according to a preferred embodiment of the present invention;

FIG. 6 schematically shows a connection manner of performing pre-bonding of insulators and metal bonding on the bonding surface of the laser unit and the driver chip according to a preferred embodiment of the present invention;

FIG. 7 schematically shows the process of pre-bonding the insulator and metal bonding on the bonding surface of the laser unit and the driver chip according to a preferred embodiment of the present invention; and

FIG. 8 shows a method of manufacturing a light source module according to a preferred embodiment of the present invention.

detailed description

In the following, only certain exemplary embodiments are briefly described. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "top", "bottom", "front", " Or The positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, Therefore, it should not be construed as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and should not be understood as indicating or implying relative importance or implying the number of indicated technical features. Thus, features defined as "first", "second" may expressly or implicitly include one or more of said features. In the description of the present invention, "plurality" means two or more, unless otherwise expressly and specifically defined.

In the description of the present invention, it should be noted that, unless otherwise expressly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection Connection, or integral connection: it can be a mechanical connection, an electrical connection or can communicate with each other; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction of two elements relation. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In the present invention, unless otherwise expressly specified and limited, a first feature "on" or "under" a second feature may include direct contact between the first and second features, or may include the first and second features Not directly but through additional features between them. Also, the first feature being "above", "over" and "above" the second feature includes that the first feature is directly above and diagonally above the second feature, or simply means that the first feature is level higher than the second feature. The first feature "below", "below" and "beneath" the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature has a lower level than the second feature.

The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are only examples and are not intended to limit the invention. Furthermore, the present disclosure may repeat reference numerals and/or reference letters in different instances for the purpose of simplicity and clarity and not in itself indicative of a relationship between the various embodiments and/or arrangements discussed. In addition, the present disclosure provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the application of other processes and/or the use of other materials.

The embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the embodiments described herein are only used to illustrate and explain the present invention, but not to limit the present invention.

In the circuit system of the lidar, the chip is connected to the printed electronic circuit board, and the main parasitic elements generated by the printed electronic circuit board (PCB) wiring include: parasitic resistance, parasitic capacitance and parasitic inductance. For example: the parasitic resistance of the PCB is formed by the traces between components; the traces, pads and traces on the circuit board will generate parasitic capacitance; the generation of parasitic inductance includes loop inductance, mutual inductance and vias. All of these parasitic elements can interfere with the effectiveness of the circuit when translating a circuit schematic into an actual PCB.

According to a preferred embodiment of the present invention, as shown in FIG. 2 , the present invention provides a light source module 20 that can be used for lidar, including a driver chip 21 and a laser unit 22 . The laser unit 22 is stacked over the driver chip 21 and is electrically connected to the driver chip 21 so as to be driven by the driver chip 21 to emit laser light.

FIG. 3 shows a partial enlarged view of the top view of the light source module 20. The laser unit 22 includes a plurality of lasers arranged in an array. The laser arrangement can be designed according to the needs of the beam shape and power. Only shown in FIG. 3 Part of the laser. The laser unit 22 is stacked on the driver chip 21, and the bonding point 222 of the laser unit 22 is electrically connected to the bonding point 211 of the driver chip 21, which can be realized in various ways: for example: (1) The laser unit 22 is welded to the On the driver chip 21 (as described in detail below with reference to FIG. 5 ); (2) the laser unit 22 and the driver chip 21 are electrically connected by means of insulating pre-bonding and metal bonding on the bonding surface (as described below with reference to FIG. 6 ) described in detail). In the connection mode (1), the bonding points 211 of the laser unit 22 and the driver chip 21 are displaced from each other, so as to be easily welded together by bonding wires, and the light-emitting surface 221 of each laser in the laser unit 22 and the laser unit 22 The bond points 222 are on the same side. In the connection mode (2), the laser unit 22 is, for example, located above the bonding point 211 of the driver chip 21, and the two overlap, and the light-emitting surface 221 of each laser in the laser unit 22 and the bonding point 222 of the laser unit 22 are located at on the opposite side.

In the embodiments shown in FIG. 2 and FIG. 3 , the present invention adopts a laminated structure in which the laser unit 22 is stacked on the driver chip 21 , and the laser generating part can be seen to be directly installed by cutting along a plane perpendicular to the surface of the driver chip 21 . On the upper surface of the control chip, the lower surface of the driver chip 21 is electrically connected to the PCB. Therefore, the laser unit 22 is not in contact with the PCB, but is directly connected with the upper surface of the driver chip 21, so the laser unit 22 and the driver chip 21 can be directly electrically connected by a suitable packaging process without going through the PCB (refer to FIG. 5 and FIG. 6 ). ), which not only reduces the parasitic inductance generated by the PCB trace, but also reduces the size of the PCB, which is beneficial to the integration and miniaturization of the transmitter subsystem.

According to a preferred embodiment of the present invention, the light source module 20 includes a multi-channel driver chip 21 and a laser array composed of a plurality of lasers. As shown in FIG. 3 , the laser unit 22 includes a plurality of laser subunits, such as the laser subunits 22-1, 22-2, . . . , 22-n shown in FIG. The light source used includes an array of multiple lasers, that is, a multi-cavity VCSEL. The corresponding driver chip 21 also includes a plurality of control channels, and the number of control channels may correspond to the number of laser sub-units, so that each laser sub-unit and a control channel of the driver chip 21 constitute an emission channel. can be controlled individually.

According to a preferred embodiment of the present invention, the light source module 20 includes a multi-channel driver chip 21 and a laser array composed of a plurality of lasers. The laser unit 22 includes a plurality of lasers, each of which can be used as a light source for one light-emitting channel, that is, a single-cavity VCSEL. Correspondingly, the driver chip 21 also includes a plurality of control channels, and the number of the control channels corresponds to the number of the lasers, so that each laser and one control channel of the driver chip 21 constitute an emission channel.

FIG. 4 schematically shows the internal circuit structure of the light source module 20 according to a preferred embodiment of the present invention. The laser unit 22 is an array composed of multiple lasers, and the driver chip 21 is a multi-channel driver chip, that is, the driver chip 21 can be used to drive multiple lasers on the laser unit 22 . The laser sub-units 22-1, 22-2, . . . , 22-n are respectively an array composed of a plurality of lasers, and the plurality of lasers in the laser sub-units can emit light at the same time and be used as a light source. The laser subunits 22-1, 22-2, . The anodes of the lasers are respectively electrically connected to the laser switching devices 214 of the multi-channel driver chip 21 .

According to a preferred embodiment of the present invention, as shown in FIG. 4 , the light source module 20 further includes a plurality of control circuits 212 , the multi-channel driver chip 21 further includes a control logic unit 213 , and the plurality of control circuits 212 pass through separate switching devices respectively. 214 is connected to the anodes 205 of the plurality of lasers 22-n, and the control logic unit 213 of the multi-channel driver chip 21 is electrically connected to the plurality of control circuits 212, thereby controlling the plurality of lasers 22-n to emit light independently through the plurality of control circuits 212.

The laser can be an edge emitting laser (EEL) or a vertical cavity surface emitting laser (VCSEL). Due to the high channel spacing of edge-emitting lasers (the common channel spacing is 1mm), the integration is low, while the vertical cavity surface-emitting laser (VCSEL) array channel spacing can reach 100 to 200 μm, which can achieve higher integration. Therefore, preferably, the laser array of the light source module 20 is a VCSEL array, such as a single-line array.

The control circuit 212 and the switching device 214 can be integrated on the driver chip 21 through a semiconductor process. Preferably, the switching device 214 is a PMOS transistor.

As shown in FIG. 4, according to a preferred embodiment of the present invention, an array composed of multiple lasers (such as VCSELs) is directly stacked on a multi-channel driver chip (driver ASIC) 21, the multiple lasers (VCSELs) share a cathode, and the cathode can be A multi-channel driver chip (driver ASIC) 21 is embedded, and is electrically connected to a ground terminal (GND) 215 on the multi-channel driver chip (driver ASIC) 21 . The anodes of each of the lasers (VCSELs) 22-1 . . . 22-n are wired to bond pads 211 on a multi-channel driver ASIC (driver ASIC) 21, respectively. The array composed of the laser (VCSEL) and the multi-channel driver chip (driver ASIC) 21 are directly stacked. The electrical connection between the laser array and the driver chip does not need to be routed from the PCB, which shortens the electrical circuit between the laser array and the multi-channel driver chip. Reduced parasitic inductance.

When a PMOS transistor is used as the switching device 214, the anode of the laser of each channel is electrically connected to the drain of the PMOS transistor 214, the base of the PMOS transistor 214 is connected to the control circuit (CTL) 212, and each control circuit 212 is respectively connected to the multi-channel The control logic unit 213 on the driver chip 21 . The control logic unit 213 can control each PMOS transistor 214 to conduct independently, so that each laser channel can emit light independently. The multiple emission channels of the light source module 20 can emit light at the same time or not at the same time, and each channel is independently controllable.

FIG. 5 shows a connection structure between a laser and a driver chip according to a preferred embodiment of the present invention. As shown in FIG. 5 , the laser unit 22 of the light source module 20 is welded to the driver chip 21 by bonding wires. As shown in the figure, the driver chip 21 is attached to the package substrate (lead frame, not shown), and the bonding point 222 of the laser unit 22 is welded to the bonding point 211 of the driver chip 21 by bonding wires. Then encapsulate the encapsulation material to form the encapsulation layer 24, the thickness of the encapsulation layer 24 is between 0.02-5mm, the encapsulation layer 24 surrounds the overall structure composed of the driver chip 21 and the laser unit 22, and emits light corresponding to the lasers of the laser unit 22. A through hole 241 is provided at the position, which is filled with light-transmitting material as a laser exit window for the laser beam L to exit. The light-transmitting material should choose a material that does not affect the beam output, such as BaF ₂ . In this packaging method, the light-emitting surface of the laser unit 22 and the bonding point 222 of the laser unit 22 are on the same side, and both are located on the upper surface of the laser unit 22 in FIG. 5 . The package substrate is electrically connected to the PCB 25 through a BGA (Ball Grid Array).

According to a preferred embodiment of the present invention, as shown in FIG. 5 , a driver chip (driver ASIC) 21 is attached to the package substrate with glue, and the bonding points 222 of the array composed of lasers (VCSELs) are welded to the driver chip with bonding wires (driver ASIC) 21 on the bonding point 211. Then encapsulate it with packaging materials to obtain a packaging module of laser (VCSEL) + driver chip (driver ASIC). A through hole 241 is provided on the encapsulation layer 24 at a light exit position corresponding to the laser (VCSEL), filled with a light-transmitting material for the laser beam to exit. The package substrate is electrically connected to the printed circuit board 25 through a BGA (Ball Grid Array).

FIG. 6 shows a connection structure between a laser and a driver chip according to another preferred embodiment of the present invention. As shown in Fig. 6, the laser is a backside emitting VCSEL, that is, light is emitted from an N-type resonator (DBR). The anode Cu electrode of each laser in the laser unit 22 and the bonding point of the driver chip 21 are electrically connected by means of hybrid bonding. In this packaging method, the light-emitting surface 221 of the laser unit 22 is on the surface of the N-type DBR, and the bonding point 222 of the laser unit 22 is the laser anode Cu electrode, which is connected to the P-type substrate of the VCSEL laser.

According to a preferred embodiment of the present invention, as shown in FIG. 6 , the array composed of a plurality of lasers of the light source module 20 and the driver chip 21 are electrically connected by means of pre-bonding of insulators and metal bonding on the bonding surfaces, That is, a hybrid bonding method is used for encapsulation. As shown in Figure 7, taking a VCSEL laser and a Driver ASIC as an example, a typical process is: the conventional metal interconnection layer process is completed in the copper back-end process, and finally stops at the chemical mechanical polishing process of the top copper interconnection layer (Cu CMP), expose the copper and dielectric layers, and then activate the surface dielectric through plasma surface activation technology. When the bonding surface of the VCSEL and the bonding surface of the driver ASIC are in contact with each other, the surface dielectric of the VCSEL and ASIC will be at room temperature. A strong physical bond occurs, followed by a further high temperature annealing process to bond the Cu-Cu electrodes together and form electrical connections, and Cu interconnects to connect the underlying ASIC circuits, thereby obtaining metal and dielectric co-bonding.

In addition, although it is not shown in FIG. 6 , those skilled in the art can easily understand that the driver chip 21 can be electrically connected to the printed electronic circuit board directly through the BGA, which will not be repeated here.

According to a preferred embodiment of the present invention, the laser unit 22 in the light source module 20 includes one or more of a vertical cavity surface emitting laser and an edge emitting laser, preferably a vertical cavity surface emitting laser VCSEL. According to a preferred embodiment of the present invention, the laser unit 22 includes one or more of a single-cavity VCSEL and a multi-cavity VCSEL.

According to a preferred embodiment of the present invention, the present invention also provides a laser radar, which includes the above-mentioned light source module 20 as a transmitting unit. When the laser radar needs to emit a laser beam for detection, the control logic unit 213 of the multi-channel driver chip 21 can drive the laser to emit light according to a certain timing sequence.

As shown in FIG. 8, according to a preferred embodiment of the present invention, the present invention further provides a method 80 for manufacturing a light source module, including:

In step S81, the laser unit is stacked on the driver chip;

In step S82, the laser unit is electrically connected to the driver chip.

According to a preferred embodiment of the present invention, the driver chip is a multi-channel driver chip, the laser unit includes an array formed by a plurality of lasers, and the electrically connecting the laser unit to the driver chip (step S82) includes:

In step S821, multiple lasers share a cathode, and the cathode is electrically connected to the ground terminal of the multi-channel driver chip;

In step S822, the anodes of the lasers are respectively electrically connected to the bonding points of the multi-channel driver chip.

According to a preferred embodiment of the present invention, the light source module includes a plurality of control circuits corresponding to the number of lasers, the multi-channel driver chip includes a control logic unit, and the laser unit is electrically connected to the driver chip (step S82) also includes:

In step S823, each laser is electrically connected to a corresponding control circuit through a switching device respectively;

In step S824, each control circuit is electrically connected to the control logic unit of the multi-channel driver chip, respectively.

According to a preferred embodiment of the present invention, in the method 80 of manufacturing a light source module, the implementation manner of electrically connecting the laser unit to the driver chip (step S82 ) includes:

(1) The laser unit is welded to the driver chip by bonding wires.

In this connection, the light-emitting surface of the laser unit and the bonding point of the laser unit are on the same side. After the electrical connection is achieved, the light source module needs to be packaged with a packaging material.

(2) The laser unit and the driver chip are electrically connected by means of insulator pre-bonding and metal bonding on the bonding surface.

In this connection mode, the light-emitting surface of the laser unit and the bonding point of the laser unit are on the opposite side.

A preferred embodiment of the present invention provides a light source module formed by stacking a laser unit and a driver chip, a laser radar including the light source module, and a method for manufacturing the light source module. The light source module provided by the present invention eliminates or reduces the need for wiring from the PCB, reduces the parasitic inductance of the driving circuit, thus realizes the emitter narrow laser pulse, improves the distance measurement performance and the distance measurement accuracy of the laser radar product, reduces the The resolution point frequency is improved, and the pressure on the human eye safety threshold is relieved. The stacking design improves the integration of light source modules, facilitates automatic assembly and production, and makes it possible to produce multi-channel, independently addressable lidars.

Finally, it should be noted that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, the The technical solutions described in the foregoing embodiments may be modified, or some technical features thereof may be equivalently replaced. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

A light source module that can be used for lidar, including:

driver chip; and

a laser unit, which is stacked on the driver chip and electrically connected to the driver chip, so that the laser can be driven by the driver chip to emit laser light.
The light source module according to claim 1, wherein the driver chip is a multi-channel driver chip, and the laser unit comprises an array formed by a plurality of lasers.
The light source module of claim 2, wherein the plurality of lasers share a cathode, the cathode is electrically connected to the ground terminal of the multi-channel driver chip, and the anodes of the plurality of lasers are respectively electrically connected to the multiple bonding points of the multi-channel driver chip.
The light source module of claim 3, further comprising a plurality of control circuits, the multi-channel driver chip comprising a control logic unit, the plurality of control circuits are respectively connected to the plurality of anodes of the plurality of lasers through switching devices , the control logic unit of the multi-channel driver chip is electrically connected to the plurality of control circuits, so as to control the plurality of lasers to emit light independently through the plurality of control circuits.
The light source module of any one of claims 1-4, wherein the electrical connection comprises soldering with bond wires.
The light source module of claim 5, further comprising:

The electrically connected light source modules are packaged with a packaging material.
The light source module according to any one of claims 1-4, wherein the electrical connection comprises pre-bonding the laser unit and the driver chip with insulating material and metal bonding.
The light source module according to any one of claims 1-4, wherein the laser unit comprises one or more of a vertical cavity surface emitting laser and an edge emitting laser.
The light source module according to claim 8, wherein the vertical cavity surface emitting laser comprises one or more of single-cavity VCSEL and multi-cavity VCSEL.
A lidar, comprising the light source module according to any one of claims 1-9.
A method of manufacturing a light source module, comprising:

Stack the laser unit on top of the driver chip;

The laser unit is electrically connected to the driver chip.
The manufacturing method of claim 11, wherein the driver chip is a multi-channel driver chip, the laser unit comprises an array of a plurality of lasers, and the step of electrically connecting the laser unit to the driver chip comprises:

the plurality of lasers share a cathode, and the cathode is electrically connected to the ground terminal of the multi-channel driver chip;

The plurality of anodes of the plurality of lasers are respectively electrically connected to the plurality of bonding points of the multi-channel driver chip.
The manufacturing method of claim 12, wherein the light source module comprises a plurality of control circuits, the multi-channel driver chip comprises a control logic unit, and the step of electrically connecting the laser unit to the driver chip further comprises:

connecting the plurality of control circuits to the plurality of anodes of the plurality of lasers through switching devices, respectively;

The control logic unit of the multi-channel driver chip is electrically connected to the plurality of control circuits.
13. The method of manufacture of any of claims 11-13, wherein the electrical connection comprises soldering with bond wires.
The manufacturing method of claim 14, further comprising:

The electrically connected light source modules are packaged with a packaging material.
The manufacturing method according to any one of claims 11 to 13, wherein the electrical connection includes pre-bonding of insulators and metal bonding of the bonding surfaces of the laser unit and the driver chip.